RRC messages and procedures

ABSTRACT

A method and apparatus for radio resource control (RRC) messaging. A method in a wireless communication system includes receiving, at a wireless transmit/receive unit (WTRU) an RRC change command including a plurality of commands from a Node B and receiving, at the Node B, an RRC change response from the WTRU, wherein the RRC change command includes a command for performing a measurement gap configuration procedure and a command for performing a measurement gap activation procedure.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/228,704 filed on Mar. 28, 2014, which issued as U.S. Pat. No.9,301,284 on Mar. 29, 2016, which is a continuation of Ser. No.13/764,528, filed Feb. 11, 2013, which issued as U.S. Pat. No. 8,688,125on Apr. 1, 2014, which is a continuation of U.S. patent application Ser.No. 12/133,514, filed Jun. 5, 2008, which issued as U.S. Pat. No.8,374,609 on Feb. 12, 2013, which claims the benefit of U.S. ProvisionalApplication No. 60/942,069, filed Jun. 5, 2007, the contents of whichare hereby incorporated by reference herein.

FIELD OF INVENTION

The present invention is related to wireless communication systems.

BACKGROUND

The Third Generation Partnership Project (3GPP) has recently initiatedthe Long Term Evolution (LTE) program to bring new technology, newnetwork architecture and configurations and new applications andservices to the wireless cellular network in order to provide improvedspectral efficiency, reduced latency, faster user experiences and richerapplications and services with less cost. LTE aims at realizing anEvolved Universal Terrestrial Radio Access Network (E-UTRAN).

There have been attempts to identify radio resource control (RRC)messages for LTE, as well as the high level structure of the proceduralspecification. In order to achieve a concise specification, some ofthose messages have been grouped together to provide similarfunctionality. Table 1 shows an example of grouping of these messages.

TABLE 1 Message Groupings No Message Details Comment/UMTS equivalents 1System Information Block Downlink(DL), SYSTEM INFORMATION BLOCK 1 . . .N 1 . . . n Broadcast Channel (BCH) 2 Paging DL, Paging PAGING TYPE 1/2Channel (PCH) 3 Radio connection request Uplink (UL) RRC CONNECTIONREQUEST Synch Channel A specific message seems needed for some scenarios(SCH) considering the size constrains for the initial uplink message 4Measurement report UL-SCH MEASUREMENT REPORT Introduction of a moregeneral purpose ‘Radio connection change request’ may still beconsidered 5 Radio connection change DL-SCH RADIO BEARER SETUP commandRADIO BEARER RELEASE RRC CONNECTION SETUP RRC CONNECTION RELEASE XXXXRECONFIGURATION Possibly also covering: CELL UPDATE CONFIRM HANDOVERFROM UTRAN COMMAND MEASUREMENT CONTROL SECURITY MODE COMMAND UTRANMOBILITY INFORMATION 6 Radio connection change UL-SCH RADIO BEARER SETUPCOMPLETE complete RADIO BEARER RELEASE COMPLETE RRC CONNECTION COMPLETERRC CONNECTION COMPLETE XXXX RECONFIGURATION COMPLETE Possibly alsocovering: HANDOVER FROM UTRAN COMPLETE HANDOVER TO UTRAN COMPLETESECURITY MODE COMPLETE UTRAN MOBILITY INFORMATION CONFIRM 7 Handover toLTE DL, other radio Specific message may be needed because of the accessconsidering the size limitations in GSM technology HANDOVER TO UTRANCOMMAND (RAT) 8 WTRU capability UL, other RAT Specific message may beneeded because of the information compact considering the sizelimitations in GSM INTER RAT HANDOVER INFO 9 DL direct transfer DL-SCHSpecific message with no AS integrity (if required) DOWNLINK DIRECTTRANSFER 10 UL direct transfer UL-SCH Specific message with no ASintegrity (if required) UPLINK DIRECT TRANSFER

As shown above, the RRC connection change command groups together anumber of commands, (e.g., Setup and Reconfiguration, security modecommands and measurement commands). There are currently no groupings forfailure messages. The only failure message is the use of an RRCConnection Change Failure command to indicate Message Failure. Groupingof such messages would require additional factors to be considered,especially in the case of the radio connection change command and theradio connection change complete.

Even though a separate RRC “Connection Change Failure” message has beendisclosed, groups of messages, such as security and setup or measurementcontrol and handover, raise a number of issues. One issue is whether thecomplete procedure fails if one part of the message fails. For example,the radio bearer setup part might fail while the security part passes,or the handover part might pass while the measurement control part mightfail. Another issue is the determination of which combination ofscenarios the procedure be declared a success. Therefore, there exists aneed for a method and apparatus for handling grouped command messages.

SUMMARY

A method and apparatus for radio resource control (RRC) messaging. Amethod in a wireless communication system including receiving, at awireless transmit/receive unit (WTRU) an RRC change command including aplurality of commands from a Node B and receiving, at the Node B, an RRCchange response from the WTRU, wherein the RRC change command includes acommand for performing a measurement gap configuration procedure and acommand for performing a measurement gap activation procedure.

BRIEF DESCRIPTION OF THE DRAWINGS

A more detailed understanding may be had from the following description,given by way of example in conjunction with the accompanying drawingswherein:

FIG. 1 is an example wireless communication system configured toimplement the disclosed method; and

FIG. 2 is an example signal diagram of the disclosed method for handlingRadio Resource Control (RRC) messages.

DETAILED DESCRIPTION

When referred to hereafter, the terminology “wireless transmit/receiveunit (WTRU)” includes but is not limited to a user equipment (UE), amobile station, a fixed or mobile subscriber unit, a pager, a cellulartelephone, a personal digital assistant (PDA), a computer, or any othertype of user device capable of operating in a wireless environment. Whenreferred to hereafter, the terminology “base station” includes but isnot limited to a Node-B, a site controller, an access point (AP), or anyother type of interfacing device capable of operating in a wirelessenvironment.

Referring to FIG. 1, a LTE wireless communication network (NW) 10comprises a WTRU 20, one or more Node Bs 30, and one or more cells 40.Each cell 40 comprises one or more Node Bs (NB or eNB) 30 including aprocessor 31. WTRU 20 comprises a processor 21. Processors 21 and 31 areconfigured to implement the disclosed method for handling grouped radioresource control (RRC) messages.

A method and apparatus are disclosed for handling partial failures orpartial completes of grouped RRC message procedures, wherein such afailure by one of a plurality of procedures within the RRC message canbe relayed to the NB without having to indicate a failure for all of theRRC procedures, including those that were successful.

In accordance with this method, when a WTRU 20 receives an RRC message,(e.g., a Radio Connection Change Command), processor 21 is forwarded themessage for processing. For purposes of this disclosure, a RadioConnection Change Command may include a plurality of RRC commands. Forexample, a RADIO SETUP, RRC CONNECTION SET UP, RRC CONNECTION RELEASEmay be included in the grouping of the RRC messages for the RadioConnection Change Command.

FIG. 2 is an example of a signal diagram for handling an RRC RadioConnection Change in accordance with the disclosed method. NB 30 sendsan RRC Connection Change Command message 200, including a group of RRCcommands, to WTRU 20. Upon receipt of message 200, processor 21 of WTRU20 initiates the RRC reconfiguration and other procedures associatedwith each of the grouped RRC commands.

Processor 21 of WTRU 20 then monitors the status of each of theprocedures that are being performed in response to message 200 todetermine whether the respective procedure was successfully completed.Once a determination has been made by processor 21 regarding eachprocedure 203, processor 21 utilizes this information to generate anindication of whether message 200 was successfully completed in itsentirety, partially completed, or failed to complete 204. In accordancewith the disclosed method and apparatus, this information is included inan information element (IE) that may be included in a response message201, (e.g., an RRC Connection Change Complete or an RRC ConnectionChange Failure).

The information relayed in the additional IE depends on the networkconfiguration. For example, the presence of the IE may indicate to NB 30that the RRC Message failed, partially or completely; that there wasonly a partial failure of the RRC Message; that the RRC Messagecompleted, partially or completely. Alternatively, the IE may alsoindicate which procedure within the RRC Message failed, as well as thereason for the failure.

The IE, called “Failed Configuration” or any other name, may holdenumerated values, such as, “setup”, “security”, “measurementconfiguration”, and the like. The failed configuration IE may alsoinclude a sub-IE called “failure cause”, which may include any otherinformation that is considered necessary and that may indicate thereasons for the failure. For example, if there is a partial failure ofthe procedure, the RRC “Connection Change Complete” message 201including the IE may be sent to NB 30 and processed by NB processor 31,indicating which part of the configuration did not completesuccessfully.

Alternatively, in the case of a partial success, WTRU 20 may send an RRC“Connection Change Failure” message 201 including an IE called“Configuration Completed”, for example, or another name that issuitable. This Configuration Completed IE may hold similar enumeratedvalues such as, “setup”, “security”, or “measurement configuration,”which indicates whether part of the configuration completedsuccessfully. Within the IE “Configuration Completed” there may besub-IEs, which may include the information from current “setup complete”or “security mode complete” commands, the uplink ciphering activationtime info or the start values, for example.

In another alternative, when there is a partial success in theconfiguration, the RRC “Connection Change Complete” message 201, as wellas details of the configuration that succeeded may be sent with an IEdesignated as “Partial Reconfiguration” or any other name that isconsidered suitable. In accordance with this alternative, the “PartialReconfiguration” IE may have a “true” or “false” value, which indicateswhether another message is set to follow. If the IE is set to true, theRRC “Connection Change Complete” message 201 may be followed by the RRC“Connection Change Failure” message which may include details of thefailed configuration.

Alternatively, the reverse may be done for a partial reconfiguration.The RRC “Connection Change Failure” message 201 may be sent first withdetails of the failed configuration, along with an IE designated as“Partial Reconfiguration”, or any other name that is consideredsuitable, which may be followed by a RRC “Connection Change Complete”message with details of the configuration that completed successfully.

Alternatively, if a configuration is partially successful, a RRC“Connection Change Failure” message may be sent and no information maybe configured. Such an action, however, may not be beneficial as thecombining of messages leads to a higher chance of failure since allparts of the configuration would be expected to pass.

In accordance with the disclosed method, an example partialconfiguration may include a situation where the RRC “Connection ChangeCommand” 200 carries both security mode information and radio bearersetup information. Where there is some failure, such as a physicalchannel failure, the radio bearer setup cannot be completedsuccessfully, but the security procedure is able to completesuccessfully. In this case, there is a partial configuration because,the security procedure would pass but the radio bearer setup informationwould fail.

Another example may be if a handover is being performed and the RRC“Connection Change” command 200 includes both handover information andmeasurement control information. A failure may occur, for example, aninvalid configuration, wherein the measurement parameters may not besuccessfully configured, but the handover may still be successful.

In another example, the handover may not be successfully completed, butthe measurement parameters are successfully configured. Successfulmeasurement control configuration, though, may not need a confirmationmessage. As such, an RRC “Connection Change Failure” message is sent toNB 30, including, an IE designated as “Configuration Completed” with avalue “measurement” such that the network does not need to send themeasurement control information again.

In accordance with the disclosed method, some instances of partialreconfiguration may not be allowed. For example, where an RRC“Connection Change Command” message including both security modeinformation and radio bearer setup information encounters a failure,such as an invalid configuration, the security mode command parametersmay not be configured. As a result of the detection by processor 21 ofthe security mode failure, an RRC “Connection Change Failure” command issent to NB 30, thereby preceding configuration of the radio bearers.This prevents a situation where the data is ready to be sent, but nosecurity is enabled.

By way of another example, the “security capability” information sent aspart of the security information may not match a WTRU's capabilityinformation. If this should occur, WTRU 20 sends a failure for theentire message and does not configure anything. There may be otherscenarios where it might be better to send a failure message and notconfigure anything.

Alternatively, the network may signal the measurement control or thesecurity mode information in the handover, setup or reconfigurationmessages with an IE indicating that the configuration of the measurementor any other such information is optional. WTRU 20 may then configurethe information or not configure the information based on its ownconstraints, such as receiving an invalid configuration or wanting to doa faster handover, for example. WTRU 20 could signal an RRC “ConnectionChange Complete” message with an optional IE, such as “Configuration NotCompleted Value”, or any other suitable name, wherein the value may be ameasurement, a setup, or any value indicating the part of theconfiguration that was not complete. This may indicate to the networkthat the network should signal the incomplete configuration to WTRU 20again. Also, if there are any parameters in the optional configurationinformation, such as measurement control, which the WTRU 20 may not haveunderstood and therefore may not complete the configuration, WTRU 20 mayalso indicate that as part of the RRC Connection Change command.

If a complete success of the configuration is detected by processor 21,an RRC “Connection Change Complete” message 201 sent without the IEincluded. An indication that none of the commands in the RRC “ConnectionChange Command” message could be configured, may be sent in a RRC“Connection Change Failure” message without the IE “ConfigurationCompleted”.

In an alternative disclosed method, the measurement control and securitycontrol information are included in a IE included in a setup orreconfiguration message, for example.

Since the security and the measurement control information are allowedto be transmitted separately as a different RRC “Connection Change”command, rather than coupling the information with the setup,reconfiguration, handover or any other command, an “Informationincluded” IE is included within the RRC “Connection Change” command.This IE indicates to WTRU 20 whether the measurement control andsecurity information is embedded in the message. The “InformationIncluded” IE may be an enumerated field and hold values for securityinformation, measurement control information, and the like. Theinclusion of such an IE in the RRC “Connection Change” command mayassist WTRU 20 with preparing to receive additional messages.

In another alternative, when information for different purposes iscombined, such as security and setup information, each of them may carryseparate activation times. In accordance with this alternative, WTRU 20stores the two separate activation times. In some cases, the activationtimes may be combined and WTRU 20 would enable the entire configurationat one specified activation time. Alternatively, when combiningmeasurement control with setup/handover/reconfiguration information, themeasurement identifier may preferably be carried so that furthermodification to the measurement information may be made by using theproper identifier.

If messages are being combined, common information elements, such asintegrity check information, for example, may be combined.

In earlier Universal Mobile Telephone System (UMTS) releases, the IE“DPCH Compressed Mode Info” was part of many reconfiguration/setupmessages. “DPCH Compressed Mode Status” IE was part of the measurementcontrol information. This IE allows the measurement control message toactivate the compressed mode, but not configure it. In this case, beforeWTRU 20 receives the measurement control command with the gap activationcommand, WTRU 20 may need to receive the compressed mode gap parametersthrough the reconfiguration message. Although there are measurement gapsin place of compressed mode in LTE, the restriction of some messagesbeing only able to activate the gap but not be able to configure it isremoved. All the measurement gap parameters may be combined into onecommon set, such as “Measurement Gap Info.” RRC messages could then usethis set to configure and activate the measurement gap. In this case,the same RRC message may simultaneously configure and activate the gapfor WTRU 20, thereby simplifying the configuration procedure.

Although features and elements are described above in particularcombinations, each feature or element can be used alone without theother features and elements or in various combinations with or withoutother features and elements. The methods or flow charts provided hereinmay be implemented in a computer program, software, or firmwareincorporated in a computer-readable storage medium for execution by ageneral purpose computer or a processor. Examples of computer-readablestorage mediums include a read only memory (ROM), a random access memory(RAM), a register, cache memory, semiconductor memory devices, magneticmedia such as internal hard disks and removable disks, magneto-opticalmedia, and optical media such as CD-ROM disks, and digital versatiledisks (DVDs).

Suitable processors include, by way of example, a general purposeprocessor, a special purpose processor, a conventional processor, adigital signal processor (DSP), a plurality of microprocessors, one ormore microprocessors in association with a DSP core, a controller, amicrocontroller, Application Specific Integrated Circuits (ASICs), FieldProgrammable Gate Arrays (FPGAs) circuits, any other type of integratedcircuit (IC), and/or a state machine.

A processor in association with software may be used to implement aradio frequency transceiver for use in a wireless transmit receive unit(WTRU), user equipment (UE), terminal, base station, radio networkcontroller (RNC), or any host computer. The WTRU may be used inconjunction with modules, implemented in hardware and/or software, suchas a camera, a video camera module, a videophone, a speakerphone, avibration device, a speaker, a microphone, a television transceiver, ahands free headset, a keyboard, a Bluetooth® module, a frequencymodulated (FM) radio unit, a liquid crystal display (LCD) display unit,an organic light-emitting diode (OLED) display unit, a digital musicplayer, a media player, a video game player module, an Internet browser,and/or any wireless local area network (WLAN) or Ultra Wide Band (UWB)module.

What is claimed is:
 1. A method for use in a Node B, the methodcomprising: transmitting a radio resource control (RRC) change messageto a wireless transmit/receive unit (WTRU), wherein the RRC changemessage includes an information element (IE) indicating both ameasurement gap configuration procedure and a measurement gap activationprocedure; and receiving an RRC change complete response from the WTRUon a condition that the WTRU performed the measurement gap configurationprocedure based on the received RRC change message and performed themeasurement gap activation procedure based on the received RRC changemessage.
 2. The method of claim 1, wherein the RRC change messageincludes a plurality of measurement gap parameters.
 3. The method ofclaim 2, wherein the plurality of measurement gap parameters arecombined into a common set.
 4. The method of claim 1, wherein the RRCchange complete response indicates for each measurement gapconfiguration procedure, whether the measurement gap configurationprocedure was completed, the measurement gap configuration procedure waspartially completed, or the measurement gap configuration procedurefailed to complete.
 5. A Node B, the Node B comprising: a transmitterconfigured to transmit a radio resource control (RRC) change message toa wireless transmit/receive unit (WTRU), wherein the RRC change messageincludes an information element (IE) indicating both a measurement gapconfiguration procedure and a measurement gap activation procedure; anda receiver configured to receive an RRC change complete response fromthe WTRU on a condition that the WTRU performed the measurement gapconfiguration procedure based on the received RRC change message andperformed the measurement gap activation procedure based on the receivedRRC change message.
 6. The Node B of claim 5, wherein the RRC changemessage includes a plurality of measurement gap parameters.
 7. The NodeB of claim 6, wherein the plurality of measurement gap parameters arecombined into a common set.
 8. The Node B of claim 5, wherein the RRCchange complete response indicates for each measurement gapconfiguration procedure, whether the measurement gap configurationprocedure was completed, the measurement gap configuration procedure waspartially completed, or the measurement gap configuration procedurefailed to complete.